铁路隧道超前管棚变形规律及参数研究  

Research on the Deformation Law and Parameters of Advanced Pipe Shed for Railway Tunnel

作　　者：黄华[1] 巩江峰[1] 邸成[1] 朱勇[1] HUANG Hua;GONG Jiangfeng;DI Cheng;ZHU Yong(China Railway Eryuan Engineering Group Co.Ltd,Chengdu,Sichuan 610031,China)

机构地区：[1]中铁二院工程集团有限责任公司

出　　处：《铁道工程学报》2019年第12期65-70,共6页Journal of Railway Engineering Society

摘　　要：研究目的:隧道近距下穿既有铁路路基或隧道段时,常采用洞内超前大管棚支护,而目前多采用工程类比法确定其支护参数,因此有必要对大管棚支护变形规律及设计参数进行研究。研究结论:(1)管棚结构变形由管棚弯曲变形和支承结构压缩变形组成,变形计算公式为s=αql(2)除未支护段外,其余段长度变化对管棚变形影响相对较小,未支护段增长,变形显著增大,且刚度越小增加幅度越大;管棚变形随着荷载的增加呈线性增长;管棚变形随着刚度增大而减小,且未支护段越长减小幅度越大,当管棚刚度较小时,刚度增大则变形显著减小,当刚度达到临界值后,增大刚度则变形减小不明显;(3)应综合考虑穿越段变形控制要求、工程投资、施工难度,合理选择管棚直径和长度;(4)本研究成果可为隧道超前管棚变形规律分析、工程设计提供理论依据。Research purposes:In the construction of tunnels under existing railways subgrade or tunnel,the pipe shed support in advance is often used.At present,the engineering analogy method is often used to determine the parameters,so it is necessary to study the deformation law and design parameters of the pipe roof.Research conclusions:(1)The structural deformation of pipe shed consists of bending deformation of pipe shed andcompression deformation of supporting structure.The formula for calculating the deformation is as follows:s=αql^4/EI+q/βk.(2)Except for the unsupported section,the influence of the length change of the other sections on the deformation of the pipe shed is relatively small,and deformation increase significantly with the increase of unsupported section,and the smaller stiffness,the greater increase;the deformation of pipe shed increase linearly with the increase of load;The deformation of pipe shed decreases with the increase of stiffness,and the longer unsupported section,the greater reduction range,and when the stiffness of pipe shed is small,the deformation will decrease significantly with the increase of stiffness.When the stiffness reaches the critical value,the deformation will not decrease significantly with the increase of stiffness.(3)In order to reasonably select the diameter and length of pipe shed,the deformation control,investment and construction difficulty should be considered comprehensively.(4)The research results will provide theoretical basis to the deformation analysis and design of pipe shed for tunnel.

关 键 词：铁路隧道 管棚 变形规律 设计参数 

分 类 号：U25[交通运输工程—道路与铁道工程]